Nature of defect centers in B- and P-doped SiO2 thin films

An electron paramagnetic resonance study has been carried out on B- and P-doped oxide films on Si. The principal defects are the boron-oxygen-hole-center (BOHC) and phosphorus- oxygen-hole-center (POHC), which are unpaired electrons on oxygen atoms with B or P in the near vicinity. Our results demonstrate that the centers are activated by hole capture. We find that holes are trapped very efficiently in both B- and P-doped dielectrics; however, electrons are more efficiently trapped in the B-doped dielectrics. We find that the electrical data can be explained by assuming that the precursor to the BOHC is negatively charged and the precursor to the POHC is electrically neutral. copyright 1995 American Institute of Physics